Heretofore, non-rigid polyvinyl chloride or polyblends comprising non-rigid polyvinyl chloride and ABS resins have been mainly used for the preparation of interior automotive sheets for use as outer skins of instrument panel pads or door trim. In the use of this non-rigid polyvinyl chloride for the purpose intended, however, there were involved such problems that because of large amounts of plasticizers present in the non-rigid polyvinyl chloride, a window glass of automobile tarnishes owing to volatilization of the plasticizers, the interior automotive sheets are deteriorated and discolored by ultraviolet light of sunlight incident through automotive windows or by thermal decomposition. Particularly, a further serious problem was that the non-rigid polyvinyl chloride sometimes undergoes brittle fracture in a cold district.
In recent years, owing to such circumstances, interior sheets prepared from polyolefin resins such as polypropylene have come to be used. However, molded articles, such as interior sheets comprising polyolefin resins had such problems that the molded articles are liable to receive scratches on the surface thereof, poor in external appearance because of excessively high surface gloss as well as in touch because of surface roughness and, moreover, the surface of said molded articles are apt to be attacked by hydrocarbon solvents.
In order to solve such problems as mentioned above, there have been made various attempts, for instance, Japanese Patent Laid-Open-to-Public Publn. No. 197741/1985 proposes a process for preparing sheets for use in interior automotive decoration, characterized in that the sheet is formed from a thermoplastic elastomer comprising a polyolefin resin and a partially cross-linked type ethylene/.alpha.-olefin copolymer rubber, and on the surface of the thus formed sheet is coated a reactive paint containing a saturated polyester resin, acrylic ester resin or an isocyanate resin.
The sheet prepared by the process disclosed in this Japanese Patent L-O-P Publn. No. 197741/1985 cannot be said to have sufficiently excellent surface characteristics, though such surface characteristics as surface abrasion resistance has been improved in comparison with the sheet obtained by said process but omitting the reactive paint coating step, and hus a further improvement in surface characteristics has been desired therefor.
The present inventors conducted extensive research with the view of obtaining molded articles of thermoplastic elastomer, such as interior automotive leather-like sheets excellent in surface characteristics, and eventually found that molded articles having excellent surface characteristics are obtained by coating a primer having a specific composition on the surface of molded articles prepared from thermoplastic elastomers to form a primer layer thereon, and then applying the aforesaid reactive paint onto the surface of the thus formed primer layer.